Computing-machine.



PATBNTED JUNE 16, 1908.

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lHARRY BURTIS, OF LAWRENCE. KANSAS.

COMPUTING-MACHINE.

f No. 890,000.

specification of Letten Patent.

Patented June 1e, 1908.

. Application ledFebruu-y 4, 1907. Serial No. 355,673.

To all it may concern:

l Be it known that I, HARRY J. BURTrs, citizenof the United States, residing at Lawrence, in the county of Douglas and Statel of Kansas, have invented certain new and useful, Im rovements in Computing-Machines, ofwhic the following is a specification.I

`M invention relates to computing devices and as special reference to mechanism adapted to register the yresults obtained in the processes of adding and subtracting numbers arithmetically.

The chief objects of my improvement are to devise a simple, compact and accurate mechanism for lthe purpose stated; to produce a combined adding and v subtracting ma'chine the operation of which will be simplev and readily understood and which can thus be 4used by an unskilled person; to design an apparatus for registering results in arlthmetical problems, having few parts and that in consequence can be economically manufactured and will not be liable to get` out of order.

My device comprises, generally speaking, a casing upon the up er'surface of which 1s imprinted series of co umns of figures which constitute the key board, a number of registering Wheels, vactuating devices consisting of bands orvbelts arranged in parallel7 means for. operating the bands, vand mechanism for carrying to, or deducting from, a higher denomination.

In the accompan ing drawing which forms a part of this speci cation for patent, I have shown my improved combined adding and subtracting machine in the following viewsz- Figure 1 is a top plan view of the complete device, a portion of the casing having been broken away and some parts removed in order, to `disclose the internal mechanism; Fig. 2 is a sectionalview taken on the line 2-.2 of 1; Fig.. 3 is a fragmentary view, partly in section to illustrate the method of carrying and deducting; Fig. 4 is a view of the right hand side of onepof the registering wheels showingone lof the transfer pinions in engagement therewith, and Fig. 5 is a view of the eft hand side of another registering Wheel. also showing one of the pinions in its relation tothe gear teeth.

Referring to the drawing in detail, 6 indicates the base plate, 7 the sides, 8 and 9 the front and rear ends, respectivel and 10 the cover of a casin within which 1s located the mechanism. T e cover is hinged at 11 to the rear plate 9 and is inclined downward from -the rear towards the front of the casing where it is furnished with a handle or knob 12, by means of which the cover may be lifted on its hinges to permit of ready access to the working parts. The said cover is rovided with a series of parallellon itudina slots 13 which extend approximate y the length of the cover, and uponeither. side of each slot and parallel therewith are arranged columns of characters 14, com rising the figures from 0' to 9 inclusive. he gures are s aced equally apart longitudinal y in the co umn and those upon one side, preferably the right, are arranged in numerical order from above downwar beginning near the top with 0 and increasing downward by increments of 1 until the digit 9 is reached. `This right hand column is-used in problems requiring addition `and is designated for convenience by a lus'siO'n 15, placed at the top of the column.

he co umn of symbols laced upon the left hand side of each slot liiiewise comprise the figures from 0 to 9 as previously stated, but arranged in reverse order, beginning with the character 0 at the bottom of the column, directly op osite the figure 9 of the plus column an increasing upward by increments of 1 until 9 is reached which coincides with the character 0 in the opposite column 15. The said left hand column is employed in arithmetical computations embracing subtraction and for this reason is designated by the minus sign 16, placed at the head of the column as in the case of those used for addition.

Near either end of the casin and extending transversely between the si e plates 7 are iixed rods 17, 18, secured to the casing by bearing plates 19. The rear rod 17 carries registering Wheels 20, arranged at intervals corres onding with the spacing of the slots 13 in tlie cover 10. The said wheels are maintained at their pro er locations by sleeves-21 which enga e the ubs 22 of the wheels 20 to prevent ateral displacement but permit them to rotate freely when actuated in the manner hereinafter set forth. The rims 23 of the said wheels are reduced in diameter.

for approximately half their width to form a sprocket24 v number whic are arranged at equal intervals 0n the face of the sprocket. The face 26 ofthe raised portion of the rim 23 has impressed thereon at re ular intervals by stamping, or otherwise, .t e numerical charrovided with teeth 25, ten in acters to 9, indicated on lthe drawing by 27.

' in said bands.

The registering wheels 4are located so that theinfaces are 1n close proximity to the cover of the casing and said cover is provided with sight apertures 27a through which a single character on said face of each wheel will be exposed to View when oppositethe opening. Each rim is provided upon one side with an internal ear 28, furnished with any number of teeth divisible by ten. I refer, however, to 'construct these gears wit one hundred teeth each, so that ten teeth will correspond with each numerical division of the face of Athe Wheel. Upon the opposite side of each registering wheel is a mutilated gear comprising a segment 29 having a less number of teeth than the number in the internal gear 28 corresponding with the said numerical division"t In this instance, the said segment gear 29 is provided with eight teeth. I have shown four registerin wheels assembled vupon the rod and four sIots 13 formed in the cover. It is evident, however, that any number desired of such wheels may be arranged in series upon the rod 17, and correspondingslots be provided in the casing by increasing the lateral dimension, and I do not Wish therefore tb be limited to the precise number of registering elements illustrated. The re istering wheels thus disposed are considere to bear denominations correspondin with their relative positions, the first whee upon the right hand being considered as units, the next to the left as tens and so on, in the manner Well known in the art.

In order to provide means for actuating y`the registering wheels, I provide endless xbands or belts 30 which pass over the sprockets 24, the teeth 25 engaging apertures 3l Midway be'tween said apertures, the spaces between which correspond with the numerical intervals of the rims 23, and necessarily also the spaces between the sprocket teeth, are located operating pins 32, which are secured to the bands 30, in any convenient manner, and pro'ect through the corresponding slot to a su cient extent to be readily grasped by the fingers. The said bands are kept taut by means of grooved pulleys or idlers 33, which are journaled .on the said rod 18 near the front of the casing, and kept from lateral displacement by sleeves 34, pinned or otherwise secured to the rod. It will-be understood that the intervals between said ,operating pins not only correspond with the numerical intervals u on the face of the reV istering wheels, but vaiso with the columnar ivision shown on the face of the cover, which face may properly be designated the key board. v

As in all-"numerical registering devices,V

provision mustbe 'made for transferring the movement of each wheel to o ne of a higher denomination during some period of the rotation of the-former, so as to turn said wheel of higher denomination one step I -orward or backward according to the character of the olpration being performed. I ,accomplish t e desired result in the following manner: In the interval between each vadjacent pairof registering wheels is mounted a short shaft or arbor 35 jo4 rnaled in a bearing 36 secured to the base p` ate. by screws 37. U on the ends of this arbor 35 and mounte lor cut integral therewithare transferpinions 38, 39, whichl mesh with the gears carried by the registerin wheels. 'The pinion 38 has ten teeth an en ages the gear 28 having one hundred teet being constantly in mesh therewith. The opposite pinion 29 has teeth which correspond in pitch with the segment gear 29. The peripheral location of the said gear 29 bears such a relation to the character 0 of its registering wheel that when this figure passes the sight aperture 27"L t'l'ie se ment 29 will engage the pinion 39 and turn it one revolution, and as the relation which the pinion 38 upon the other end of the arbor ears to the gear 28 is 1 to 10, the registering wheel corresponding to that' individual gear will be given one tenth of a revolution, thus bringing another figure before the corre'- sponding sight aperture. To explain the method of using the apparatus to register the totals of arithmetical additions and subtractions, I will first fle-- scribe its application -for addition: Supposing all the registering wheels to be arranged so that 0 shows opposite each sight aperture, and it is desired to add the numbers 97 and 3,

the operator grasps the in which projects t through the tens slot, w ich is the second from the right and is opposite the 0 in the right hand or plus column, and moves it downward until said pin is directly op osite the digit 9 in the same column, whiclli was the numeral to be added. This movement of the band by means of the pin will turn the corresponding registering wheel nine tenths of a revolution and bring the iigure 9 on its face opposite the sight opening. Releasing the pin in the tens column the o erator will then gras the pin in the units s ot op osite the 0 of tlie plus column and move it ownward as before until it is opposite the digit to be added, which is 7. The units wheeI will now register 7 in its sight opening. To complete the computation by the addition of 3 the operator takes hold of the pin in the units column opposite the right hand 0, as before and moves it downward until o posite 3 in that column. The units whee will now show 0 and the tens wheel will have been moved one ste by the action of the transfer gears and the iundreds wheel willlalso have been moved one division and the digit 1 will ap ear before the aperture g thus the device wi register 100. t It will be seen lthat in the'process of addition the pin opposite the 0 in the right hand column is always theone tovbe grasped and is to be moved downward until opposite that fi re in thecolumn which it is desired to f In subtraction the result` is reached by a reversal o 'I' the o eration for adding except that the left hand column is the one used as the indicator. Thus the o erator grasps the pin opposite the 0 in the eft hand-column and moves it upward until it is. directly o 'posite theure ,which it is desired to su tractfr'om t at column thus reversing the rotary movementfof'the registering wheels. The action'of the segment-gear will be to -turn the wheel of the next' higher denominationone ste backward as it passes the transfer pinion t us deducting one unit on that wheel at'each reverse revolution of the operated wheel.

It is obvious that minor changes maybe .made inthe mechanical parts of my device .as herein disclosed without departing from the scov e'and s irit of my invention and I do not wis there ore, to be limited Ito the precise details of construction set forth.

Having thus described my invention what I claim is:-

--'1. Ina computing device, the combination witha casing provided with a plurality of parallel slots,`and furnished with indicating characters arranged adjacent to said slots, of a series. of registering elements, each element consisting of a rim having a reduced portion, a hub connected to the rim by a web formed integral with both rim and hub, an internal gear carried onone rimupon one side and a segmental" gear carried upon the opposite side of each element, means for transferring the movement lof each registering element` to the next higher denomination, and endless metal bands traveling around said reduced portions of the, registering elements, spaced pins attached to said endless bandsand projecting through said slots in 'the casing.

2. A computing device, including a series of registering elements, each element comosedf-v of a' rim, a hub connected to the rim by a web,v an internal gear carried by the rim, endles'shrnetal bands traveling'around said rim, spaced 'pins attached to said endless bands, transfer shafts arranged between adjacent regi'sjjtening elements, pinions mounted upon each-Tof?I said shafts, one .pinion en- 'gaging the internal gear of a registering ele* ment-:and the other pinion adapted to b e vTengaged-"by the element of next lower denomitolnia casing plate provided with longi* ijpdinal'vparallel slots, land indicar-1n g characters 'arranged adjacent to sald slots.

60 3.1y Ina computing machine the combinaion vmviththe casing, of a number of wheels lin presence of two witnesses.

each wheel domposed of a rim having a portion reduced in diameter and provided with jecting through` slots in said casing.

4:. In a computing device, the combination Awith'the casing of a series of registering elements com osed of a rim having a reduced portion, a ub, a web connecting said hub and rim and joined integrally therewith, a complete internal gear formed in one margin of said rimand an incomplete internal gear formed in the kother margin of said rim, a'

seriesof endless flat metallic bands traveling around land operatively engaging the faces of the. reduced portionsof-the rlms, transfer' shafts journaled in posts located between ad jacent registering elements, a pinion mounted upon one end of said shaft and engaging the complete gear of one elenient, a toothed wheel carried upon the otherend of the shaft and adapted to be engaged by the incomplete gear of another element, and a casing plate provided with Vlongitudinal parallel sjots and figures arranged adjacent to said s ots.

5. In a computing machine, the combination with the casing, of a series of registering elements composed of a rim having a reduced portion, a hub, a web connecting said hub and rim, said hub, web and rim being formed integrally, a complete internal gear formed in one margin of said rim, a series of endless flat metallic bands traveling aro'und and operatively engaging the faces of the reduced portions of the rims, transfer shafts journaled in supports located between adjacent registering elements, a pinion mountedl upon one end of each shaft and engaging the complete gear of one element,4 a toothed wheel carried upon the other end of the shaft and adapted to be engaged by the element of lower denomination, a series of grooved idlers adapted to be engaged by said endless bands, and a casing plate provided with longitudinal parallel slots and furnished with columns of figuresl arranged upon opposite sides of said slots.

In testimony whereof I allix my signature HARRY.k J'.`BURTIS. Witnesses M. R. AMERMAN, R. R. CooK.

lspaced pins attached tov said bands and pro-l 

